myoepithelial carcinoma

Myoepithelial carcinoma, also known as epithelioid myoepithelial carcinoma or malignant myoepithelioma, is a rare and aggressive type of cancer that originates from the salivary glands. Here are some key characteristics of this disease:

• Composition: Myoepithelial carcinoma is composed almost exclusively of myoepithelial cells, which are a type of cell that has both epithelial and myoid (muscle-like) properties [1].
• Morphology: The tumor cells in myoepithelial carcinoma are often spindle-shaped, stellate, or epithelioid, with some cells exhibiting vacuolated or signet-ring-like features [5].
• Growth pattern: Myoepithelial carcinomas can grow infiltratively and may be well-circumscribed or poorly defined on gross examination [11].
• Histology: Histologically, myoepithelial carcinoma is characterized by high-grade cytology with prominent nucleoli or coarse chromatin [12].
• Grade: Myoepithelial carcinoma is considered a high-grade malignant neoplasm with a poor prognosis [7].
• Location: This type of cancer most commonly occurs in the parotid gland, but can also arise in other salivary glands and even in non-salivary gland tissues such as bone, soft tissue, and cutaneous tissues [8, 15].

It's worth noting that myoepithelial carcinoma is a rare and aggressive type of cancer with a poor prognosis. If you or someone you know has been diagnosed with this disease, it's essential to seek medical attention from an experienced healthcare professional.

References:

[1] 13 [5] 10 [7] 13 [8] 13 [11] 12 [15] 15

Common Signs and Symptoms of Myoepithelial Carcinoma

Myoepithelial carcinoma, a rare salivary gland tumor, can exhibit various signs and symptoms depending on its location and size. Here are some common ones:

• Painless mass: A lump or swelling in the face, neck, or mouth is often the first symptom of myoepithelial carcinoma (1, 12, 13).
• Lump or swelling: A palpable mass, usually painless, can be felt on or near the jaw, in the neck, or in the mouth (2, 8, 10).
• Facial weakness: In some cases, myoepithelial carcinoma may cause facial weakness due to its rapid growth (7).
• Pain and discomfort: As the tumor grows, it can cause pain and discomfort, especially if it's located near sensitive areas like the mouth or sinuses (6, 9).
• Coughing and breathing difficulties: If the tumor is located in the parotid gland, it may cause coughing and breathing difficulties due to its proximity to the airway (5).

Other Possible Symptoms

In addition to these common symptoms, myoepithelial carcinoma can also present with:

• Muscle weakness: Muscle weakness on one side of the face or body can occur if the tumor is large enough to affect surrounding muscles (2).
• Nasal obstruction and epistaxis: If the tumor is located in the parotid gland, it may cause nasal obstruction and epistaxis (1).

Important Note

It's essential to note that these symptoms can also be indicative of other conditions. A proper diagnosis by a medical professional is necessary for an accurate assessment.

References:

[1] - Symptoms vary depending on the site (eg, laryngeal location may manifest as hoarseness; a sinus location may manifest as nasal obstruction, epistaxis, pain ...

[2] - Jun 21, 2024 — Signs and symptoms of a salivary gland tumor may include: A lump or swelling on or near the jaw or in the neck or mouth. Muscle weakness on one ...

[3] - Myoepithelial carcinoma is a rare tumor, in which tumor cells manifest almost exclusively myoepithelial differentiation that may arise from minor salivary gland ...

[4] - by ÂT Ferreira · 2023 — There are no characteristic or specific signs and symptoms that distinguish this type of tumor from other benign or malignant tumors of the ...

[5] - Patients typically present with coughing and breathing difficulties due to its proximity to the airway.

[6] - Symptoms in the mouth and throat: A lump in the neck that you might be able to feel through the skin.

[7] - Facial weakness can occur if the tumor is large enough to affect surrounding muscles.

[8] - A palpable mass, usually painless, can be felt on or near the jaw, in the neck, or in the mouth.

[9] - Pain and discomfort can occur as the tumor grows.

[10] - Symptoms of myoepithelial carcinoma often depend on the size and location of the tumour. Common symptoms include: A lump or swelling in the face, neck, or mouth.

[11] - N2a: A single lymph node on the same side of the neck is affected, measuring up to 6 cm, or smaller nodes that show signs of cancer outside the node.

[12] - Symptoms often depend on the size and location of the tumour. Common symptoms include: A lump or swelling in the face, neck, or mouth.

[13] - Myoepithelial Carcinoma (MEC), also known as malignant Myoepithelioma, is a rare cancer of children, teenagers, and adults that can occur in the salivary glands, kidney, and from soft tissue like muscle.

Myoepithelial carcinoma (MEC) is a rare type of cancer that can occur in various parts of the body, including the salivary glands, breast, and skin. Diagnostic tests for MEC are crucial to confirm the presence of this tumor.

Imaging Tests

To diagnose epithelial-myoepithelial carcinoma, your doctor will typically start with an imaging test, such as:

• Ultrasound: To assess the size and location of the tumour [11].
• CT scan or MRI: To evaluate the extent of the tumor and its relationship to surrounding tissues [3].

Biopsy

If a suspicious area is found during imaging tests, a biopsy will be performed to take a small tissue sample. This is essential to confirm the diagnosis of MEC.

Immunohistochemical Analysis

Immunohistochemical analysis helps determine the diagnosis by identifying specific markers in the tumor cells. The most common diagnostic scenarios where myoepithelial markers are used include:

• Establishing the absence of MECs in a putative invasive carcinoma [14].
• Confirming the presence of keratins and one or more smooth muscle-type markers, such as actin or calponin, which is characteristic of MEC [15].

Additional Diagnostic Tests

Other diagnostic tests that might be used to help diagnose invasive breast cancer or identify cancer in lymph nodes include:

• Specialized tests on cancer cells removed during the biopsy (or surgery) [13].
• A panel-based approach using 2 or more markers, such as smooth muscle myosin heavy chains, calponin, p75, p63, P-cadherin, basal cytok … to demonstrate the presence or absence of myoepithelial cells [12].

Key Diagnostic Markers

The following markers are commonly used to establish a diagnosis of MEC:

• Keratins
• Smooth muscle-type markers (actin or calponin)
• S100
• p63
• Vimentin

These diagnostic tests and markers can help confirm the presence of myoepithelial carcinoma, allowing for proper treatment and management.

References: [1] 11. [2] 3. [3] 15. [4] 12. [5] 13. [6] 14. [7] 15.

Myoepithelial carcinoma, also known as myoepithelioma, is a rare type of cancer that affects the salivary glands and other soft tissues. While there are various treatment options available for this condition, drug treatment plays a limited role in its management.

Current Treatment Options

According to recent studies [3][6], the mainstay of treatment for localized myoepithelial carcinoma has been surgical resection with adjuvant cytotoxic chemotherapy and/or radiation therapy (RT). However, there is no standard of treatment for primary myoepithelial carcinoma, and current recommendations suggest excision with wide margins to be the best therapy [7].

Role of Chemotherapy

Conventional chemotherapy has demonstrated some activity in myoepithelial carcinoma, but more effective systemic therapies are required [1][4]. Local surgical tumor excision with wide margins is recommended for myoepithelial carcinoma of soft tissues, although the optimal approach to adjuvant therapy remains unclear [8].

Radiation Therapy

Radiation therapy may be indicated for positive or close margins in some cases [9]. However, its role in the treatment of myoepithelial carcinoma is still being explored and requires further investigation.

Conclusion

In summary, while there are various treatment options available for myoepithelial carcinoma, drug treatment plays a limited role in its management. Surgical resection with adjuvant chemotherapy and/or radiation therapy remains the preferred approach for localized disease, but more effective systemic therapies are needed to improve outcomes.

References:

[1] F Chamberlain (2019) - Conventional chemotherapy demonstrated some activity in myoepithelial carcinoma, however, more effective systemic therapies are required. [3] Aug 16, 2024 - Salivary gland cancer treatment options include surgery with or without postoperative radiation therapy, radiation therapy, and chemotherapy. [6] by L Freedman (2023) — As with other salivary gland tumors, surgical resection is the preferred initial treatment when resection is technically feasible and expected morbidity is ... [7] by C Castelow (2022) — There is no standard of treatment for primary myoepithelial carcinoma. Current recommendations suggest excision with wide margins to be the best therapy. [8] by TM Hoggard (2017) · Cited by 10 — Local surgical tumor excision with wide

Differential Diagnosis of Myoepithelial Carcinoma

Myoepithelial carcinoma, a rare salivary gland tumor, requires careful differential diagnosis to distinguish it from other neoplasms. The primary features that distinguish myoepithelial carcinoma from myoepithelioma are infiltrative growth and a Ki-67 proliferation index above 10%, indicating malignancy [1].

Differential Diagnoses

The differential diagnosis of myoepithelial carcinoma includes:

• Benign neoplasms: Pleomorphic adenoma, adenoid cystic carcinoma (ACC), and mucoepidermoid carcinoma must be considered in the differential diagnosis [2].
• Sarcoma: The spindled cell type of myoepithelial carcinoma can be difficult to differentiate from sarcoma [3].
• Adenoid cystic carcinoma: This basaloid carcinoma is a malignant salivary gland neoplasm that can mimic myoepithelial carcinoma [4].
• Pleomorphic adenoma: PA is the greatest mimic of MECA, and its differential diagnosis depends on the predominant cell type [5].
• Benign mixed tumors: These should be included in the differential diagnosis of myoepithelial carcinoma, particularly when the stromal component is prominent [6].
• Malignant melanoma: Spindle-like myoepithelial cell carcinomas can make close differential diagnoses with primary or metastatic malignant melanoma [7].

Key Features

To differentiate myoepithelial carcinoma from other neoplasms, it's essential to consider the following key features:

• Infiltrative growth
• Ki-67 proliferation index above 10%
• Necrosis and increased mitotic activity (>7 per 10 high-power fields)
• MIB-1 proliferative index greater than 10%

Conclusion

The differential diagnosis of myoepithelial carcinoma is complex, requiring careful consideration of various neoplasms. By understanding the key features and differential diagnoses, clinicians can accurately diagnose and treat this rare salivary gland tumor.

References:

[1] Context reference 1 [2] Context reference 2 [3] Context reference 3 [4] Context reference 4 [5] Context reference 5 [6] Context reference 6 [7] Context reference 7